#14339: GHC 8.2.1 regression when combining GND with TypeError (solveDerivEqns: probable loop) -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler (Type | Version: 8.2.1 checker) | Keywords: deriving, Resolution: | CustomTypeErrors Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): This is technically my fault, since this regression first started happening in 639e702b6129f501c539b158b982ed8489e3d09c (`Refactor DeriveAnyClass's instance context inference`). That being said, I don't have any inclination as to what part of that patch tickles this panic. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14339#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler